What is a family preference category? Qualified relatives of a U.S. citizen or permanent resident who are not known as an immediate relative may have to wait for a visa to become available before they can apply for permanent residency. These categories are known as Preference Categories and include:
Sedimentary rocks are formed by sediment that is deposited over time, usually as layers at the bottom of lakes and oceans. This sediment can include minerals, small pieces of plants and other organic matter. The sediment is compressed over a long period of time before consolidating into solid layers of rock. Sedimentary rocks forms layers called strata which can often be seen in exposed cliffs.
Sedimentary Rocks. Sedimentary rocks are rocks composed of sediment. Sediment is deposited in a number of environments of deposition, by both moving air and moving water. Sedimentary rock identification is primarily based on composition. Texture will still be used but in a different sense than for igneous rocks.lastic sedimentary rocks contain clasts. These are fragments or pieces of rock or minerals. The composition of clastic sedimentary rocks is divided into three types-clay/silt, sand and gravel. Clay and silt are less than 1/16 mm. These are not visible to the unaided eye.